Circuit-controlling apparatus.



V J. P. KELLY. CIRCUIT GOII'IROLLING APPARATUS.

APPLICATION FILED AUG.27, 1910.

1,041,294, l Patented 0611.15, 1912.

3 SHEETS-SHEET 1.

J. F. KELLY. CIRCUIT GONTROLLING APPARATUS.

APPLICATION FILED AUG.27, 1910.

Patented Oct. 15, 1912.

3 SHEETS-SHEET 2.

J. F. KELLY. CIRCUIT GONTEOLLING APPARATUS. APPLICATION FILED AUG. 21. 1910.

Eff-L UNITED STATES 4PATENT OFFICE.

JOHN F. KELLY, OF PITTSFIELD, MASSACHUSETTS.

CIRCUIT-CONTROLLING APPARATUS.

Specification of Letters Patent.

Patented Oct. 15, 1,912..

Application led August 27, 1910.v Serial No. 579,218.

To all .whom 'it may concern:

Be it known that I, vJOHN F. KELLY, a citizen of the United States, residing at Pittsfield, county of Berkshire, and State of Massachusetts, have invented certain new land useful Improvements in Circuit-Controlling Apparatus, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

This invention relates to controlling devices for electric cir uits, and has been mader especially with the yidea of providing an improved transmitting or circuit-controlling mechanisn'i for electrically-operated playing apparatus for pianos or other key-board musical instruments, although. the invention, broadly considered, will be found useful for other purposes.

The ob]ect of the invention is, generally, to provide a circuit-controllin device which vshall be reliable and practica ly instantaneous in action, convenient to fuse, and simple and inexpensive in construction, the simplicity and clieapness of construction'being especially noticeable in the case of circuitcontrollers for controlling a large number ofl branch-circuits from a single main or supply circuit., Because of these advantages, and of others hereinafter referred to, the invention is :of especial value in its adaptation to circuit-controlling mechanisms of automatically-controlled electrically-operated playing-apparatus for pianos or other musical instruments.

In accordance with my invention I employ a body of mercury or other suitable liquid conductor as the electiode which moves to make and break contact, and control the movement of the mercury or other liquid conductor by aperforatedsheet of y paper orot-her suitable non-conducting material which is moved beneath a guiding surface which is 'below the surface level 'of the includin liquid and Awhich isprovided with one or more contactterminals or electrodes. lVhen the paper sheet intervenes between the liquidl and a particular terminalthe circuit rupted, ut when a perforation comes opposite that terminal" the liquid moves 'into cont-act therewith and the circuit isfclosed' that particular terminal is interterminals or electrodes in position to be en- .l

gaged by the mercury when such engagerrilent is .not prevented by the interposed s eet. guiding device and 'between its guiding surface and the mercury, whenever a perforaltion in the sheet comes opposite a terminal in the guiding device, the mercury will'make contact 'through the perforation with such terminal and close the circuit in which the terminal is connected, and when the sheet is moved to carry such perforation beyond such terminal the body of mercury will be cut oit' from contact with the terminal and Y the circuit opened. The closing of the cir'-- cuitr or circuits will thus be controlled` according to the movement of the-perforated sheet and the location of the perforations therein; and in applying vthe invention to electrically operated playing apparatus for musical instruments the controlling sheet will be the usual`perforated music sheet having the perforations arranged in the'usua-l manner according to the positionof the .electrodes connected in the operating circuits and according to the tones to be sounded. The alziparatusv is provided with means for automatically lifting the guiding bar and reversing thel movement .of the *oerforated sheet atthe end ofthe forward orl operative movement of the sheet, and' iii- As the sheet is' moved beneathI the cludes other features of construction, all as y hereinafter fully described.

A full understanding ofthe invention can best be given by a detailed descriptioriof a:

construction embodying the same-inzlthe preferred form, and such adesclription will nowl e accompanyp v be given'in-A connection with t ing drawings, whichr show so much as is necessary to illustrate the invention 'of a transmitting -and playing apparatus for pianos or other key-board musical instruing the electrical connections of the apparatus shown in thepreceding views and showing also/a portion of a key-board of a piano and operating magnets .tor actuating the keys.

Referring to the drawings, Fig. 6 shows at the top a series oi finger keys 2 representing a portion ofthe keyboard of a.' Key-operating magnets 3 are'lo-.z

piano. catedfbeneath the key-board, a magnet beging provided for each key in the actual apparatus. The key operating magnets, as shown, are of Vthe two-pole form shaving a pivotal oscillating armature 11 mounted between the poles, and the armature of each magnet is connected with the underside of its corresponding key by connecting rods 12 whereby when any. magnet is energized and itsarmature rotated the key with which the armature is connected will be drawn downward to cause the operation of the corresponding tone producing Iievice onthe piano. Each of .the key operating magnets' 3, is electrically connected through a'. wire a with one of a series of cont-act terminals 10 4o ofthe circuit controlling 'or transmitting mechanism of the apparatus, through which connection may be made as hereinafter described with a battery B or other suitableA source of electrical energy, and each mag- 5 net is also connected through a Iwire b with the other pole of the battery, the magnets being thus locatedin 'independent branch circuits controlled by the transmitting or circuit controlling mechanism-wh ich will now be described.

'f A bodyfof mercury or other conducting,

liquid 2O which forms thevliquid'electrode is contained in alcomparatively ylong and narrow and, preferably shallow.trough.like receptacle or holder 21,. and is in electrical connection with the battery B or other source of' electrical. energy through a main or supply wire c. Mounted `to extend lengt-hwiss ofthe troughis, a guide bar or tracker v ,b\r `22, the lower. part ol which, when it is inoperative position, extends downward .into-,the mercury inthe trough.- The con-E tact4 terminals or electrodes are formed by' 'mounted in openings extending through 66 fih'agtzacker bar with their lower ends in a line in the surface of the tracker bar which .is below the surface level of the mercuryl w n the tracker bar' is in operative positilor, and the terminal rods extend downward in the hole's to or near to the lowerv 70 surface of the tracker bar, and as sho in Figs. 3, 4 and 6 they extend down flush with the lower surface of the bar.

The lower surface of the tracker bare3-.-

tends horizontally lengthwise of the mercury holder and the lower part of the bar is semi-cylindrical or of other suitable shape in cross-section to provide a convexly curyed guiding surface against which the perl forated controlling music sheet 23 runs as 80 it is moved through the mercury beneath the bar. The controlling sheet is the so-called music sheet having note perforations 24 which are arranged crosswise of the sheet according to the position of the contact terminals 10 and theirarrangement with respect to the operating magnets and accordling to the tones to be sounded, and lengthwise of the sheet according to the time and succession of the tones, and which perforations vary in length according to the time velue of the notes which they represent. The sides of the mercury holder as shown extend upward and curve outward to form spreading or'smoothing surfaces 25 and 26 95 against which the music sheet may run as it passes toand from the tracker har. The music sheet is drawn in its playing movement from a let-olf -or carrying spindle or roller 27 over the first spreading or'smoot y110| ing surface 25, thence under the tracker bar 22 and between it andithe mercury, and thence over the spreading or smoothing' surfa'ce 26 to a wind-up roller 28.

It will be seen that the path ofy the music sheet is practically a sinuous one in its movements to and from the'- tracker-baras it' passes over the spreading or smoothing surface 25 down into the mercury under and" in Contact with the lower surface of thev 119 tracker-bar,v and up over the other spread-l ing or smoothing surface 26 to the windingA roller 28.

The tracker barj is mounted to have an upward and downward movement which is' 115 preferably a verticalone inthe same plane,

being for this purposeformed .or proiided' at its ends with rend i pieces 30 which are shaped to slide in vertical guide-ways 31 ,and

which also have outwardly extendin 'co1- 13 lars which receive andfslide on vertica lposts lor standards 32; The guide-ways'l inthe construction shown fare formed ,in 'plates 83 which form the/ends of the mercurytrough and-which are secured to the main supports 3 4. The tracker barnorxnally stands in its eleyated position, as shownl'in Fig. 5, in fwhlch position'` its lower. surface. is preferably aboye the plane of the crests of'the v spreading and smoothing surfaces 25 and 26, 13

turned. to move tive position.

sc osito permit of the `ready passing of the music sheet beneath the tracker bar in threading the sheet into the apparatus, and of its movement beneath thev bar out of en "5 ga iment therewith in rewinding vThe tra i. bar is held in its normal or raised position by suitable springs 35, and is moved downward against the pressure of the springs into` operative position by means of cam l, levers 36 which are carried by and secured .20 low the surface level of the mercury in the trough, and when moved to thisposition the shaft and cams are locked against return movement by a spring latch 40, which thus serves to lock the tracker barv .in its opera- VVhen the latch' l0 is retracted, the shaft 37 is rocked by springs lll tocretnrn the cams to the position shown in Fig. 5, and the tracker bar being thus released is then returned by 4its springs 35 vto its normal or raised position For edecting the automatic raising of tbe tracker bar at the end of the playing movement of the music sheet, means controlled by the music shcet'are provided for retract- 85 ing the latch 40, andvfor this purpose a magnet 4t2 is provided which is connected in a l c1rcu1t including one of the contact terminals 10 with which the mercury comes into corrV tactthrough a special perforation in the. 40 mus1c sheet. The circuit to this magnet as shown in Fig. 6 is from the battery B through the main switch M by wire c to the mercury in the trough 21, thence through terminal 10 at the left in Fig. 6 and wired to the magnet, and thence back to the opposite pole of the battery by Wire e.

The music sheets used in theapparatus are rolled for transportation land for introduction into the apparatus onto a carrying reel or roller in the usual manner, such rolls serving as the let-.off -and rewinding roll when introduced into'the apparatus. As shown, the carrying roll 27 is formed iwith axial recesses orl sockets in its ends, the

56 socket at. one end being formed to receive a key stud 50 of Hat or other suitable form on the end of a shaft 51, and the socket in the other end of the roll being formed to receive the end of a spindle 53 which is movable 60 endwise against the pressure of a. spring 54 to permit the roll to be placed 1n position. in

the usiealmanner, said shaft 50 and spindle 53 being iourualed in bearings in the suporting frame Se; at one side of the tracker Ehe winding roll 28 is carried bv a music sheet thereon.

shaft 55 journaled in bearings in the *supporting frames 3st at the opposite side of the tracker-bar from the carrying or let-olf reel. The winding roll is driven for druiving the music sheegpast the tracker bar by means of an electric motor geared to a countershaft 6l' from which the roll shaft 55 is driven through a belt 62 running on a pulley on the eou'ntershaft and on a pulley 63 mounted to run freely on the shaft `55, and which is clutched to the shaft-to drive the same by a clutch disk 64, which is mount-- ed to turn with and is free to slide on the shaft and has' a tapering peripheral face to engage a corresponding tapered inner face of the flange of the pulley 63 and is normally held in'its driving position, as shown in Figs. 2 and 6, by means of a spring 65. A magnet 66, having preferably a U or other suitable shaped core7 is mounted in position music sheet thereon. the roll shaft 51 is driven from ti/(e shaft 6l by a belt 70 running on a pulley on the shaft (3l and also on a pulley 7l mounted free to rotate on the shaft 51. For clutching the pulley 71 to the shaft 5l, a .clutch disk 72 similar to the clutch disk (il is mounted to rotate with and free to move endwise on the shaft, and is pressed by a spring T3 to move into its clutching or operating position and is retracted to the position shown in Figs. 2 and 6 to disconnect the. shaft 51 from the pulley 71 by a magnet 74 similar to the magnet- 66.

The circuits to the clutch magnets 66 and 74 are controlled automatically so that when the main switch M is closed and the tracker baris in its lower or operative position the magnet 74 will be energized to disconnect the shaft 5l from its driving pulley 7l and the circuit to the magnet 66 will be open so that the shaft 55 of the Winding roll 28 will be driven by the motor; and when the tracker bar is in its raised position the magnet 66 will be energized anli the circuit to the magnet 74 will be open, so that the shaft 55 will be unclutched from its driving pulley G1 and the shaft 5l will be driven to rotate the carrying roll 27' for rewinding the For thus automatically controllingthe circuits to the clutch magnets, normally closed circuit s breaking.

devices 8O and 81 are provided in the circuits to the magnets 66 and T4, respectively.

fio'

one of thei'end pieces 30 of the tracker bar and operated to break the circuit to magnet tery B, wire f leads to the magnet c'oil, and

)from the magnet coil wire g leads to the circuit breaking device 81 from which wire h leads back through the main switch vM to the other pole of the battery. The circuit of the magnet 66 extends from the battery through wires f and z' tothe magnet coil and thence through-wire k to the circuit breaking device 80 and thence by wires Z and h back through the main switch to the other pole of lthe battery. The motor circuit is also controlled by the main switch M, the motor being preferably, 'as' shown, supplied by `the lsame battery or "other source of electrical A aguets 3, the clutch magnets an r the niag- :rnet 42 which releases the tracker bar catch.

' InV the operation of the apparatus, a music roll comprising the roller 27 and a music sheet wound. thereon is placed in position, sup orted by the key studv on the end of the sha 51 and by the spindle 52, and the free 'end of the music sheet is threaded .through between the tracker bar and the mercury and secured in any usual or suitable way to the winding roll 28, the tracker bar being in nncrgy which supplies tlie key ypperating' 'its normal raised position` as shown in Fig. i

5, and the main switch M being open. The .handle 88 is then turned to depress the tracker bar to its operative position, as shown in Figs. 3 and 4, therebyforcing the music sheet downward and bringing theA lower surface of the tracker bar an the portion of the music sheet beneath it below the surface level of .the mercury in the trough. The main switch being then blosed, theroll y 28 will be driven by the motor to draw the sheet beneath the tracker bar, and the `ciri 'cuits to the dierent key operating magnets willA be closed according to the arrangement. of the controlling slots or perforations in' the music sheet 1n the following mannen' As the sheet 'runs underneath the curved- "surface of the tracker bar, it will .be held in close contact with such surface in the line-of and for a dist-ance on either side of the line ofthecontactterminals 10, and will, there-- tore, so long as a`solid 'portion of the sheet is passing beneath the bar prevent the mercury, which is under pressure beneath the bar and thereby tends to move into contact with the contactatermnals, fromreachng and makingontact with the contact .term'if nals. When, however, any perforation in the music sheet comes beneath any one of the Y contact terminals, a portion of the mercury which had valready filled the Aperforation will immediately make contact with such cont-act terminal to close circuit to the operating magnet which is connected withsuch contact terminal through one of the' branch lines a, and such magnet will therebybe energized'to operate the corresponding soundlproducing device of the piano to cause soundingof the tone' represented by that particular perforation in the music sheet. Phe circuit to this particular operating magnet will then remain closed through the contact terminal and the mercury so long as this articular note perforation in the mu sic slibet is passing beneath the contact ter'- minal, and as the perforation with its porthe tion of mercury, is carried forwardrby the cgntinued movement of the music sheet, and passes beyond the contact terminal accesi;v Bf

the mercury to the contact'terminal will cut oil and the circuit to the operating .mag-4A net suddenly broken. In the same manner,

as each note perforation in Athe music sheet crosses the' line of the contact terminals at I the bottom of the tracker bar, circuit will be completed to the corresponding operating magnet 'to cause the sounding of the tone' represented by such perforation and will remain closed for a time correspondingto the whole or full length of the perforation. When theimusic sheet has' been given its full movement and the 'last note perforation'` has passed beyond the line of the contact terminals inthe tracker bar, the circuit to tht releasing' magnet 42 will be closed b .c s ecial perforationv or that purpose as ereiiibe'fo're explained, 'and bythe action of this magnet the tracker bar wilLbe released and will then be' iin- .medately returned by its lifting .springs to its normal orraised position, and by the upward movement' of ther .tracker bar the windingroll will be disconnected fromA the 'motor and they cai-ying or rewinding roll 27 vconnected to. be ldriven by 'the motor, thus-'reversing the'movement of the music sheet and causin it to be rewound on its carrying roller 2 During such rewindiiig movement the sheet vwill run freely between l the mercury and the tracker bar'and pireferably' out f engagement with both. "At the endof the rewind, the main switch will be thrown tostop the motor, and the operative parts of the apparatus will be in position-to permit the removal nlthemusic roll tion of a new roll.`

The Velectrodes or Contact terminals alb' must be insulated from each other, ,ibi course, and tor purpose which has just been played and the inseri-- i may be made of a suitable insulating Inat-erial, such as Wood. The receptacle or holder 2l, as Well as the contact terminalsl '10,will usually be made of metal, and when vvill not readily form an 'amalgam with the mercury. As the perforated music sheet leaves the mercury and runs up over t-he spreading or smoothing surface '26 it tends to Vlift mercury in its perforations. To .prevent the Waste and diffusion of mercury, by restoring to the trough any mercury so lifted, a rittie or minor trough 90 is formed near the crest of the guiding surface 26 over Which the music sheet passes in leaying the mercury during its playing movement. The' ritlie or minor trough drains 'back into the main trough through end channels 91. Any mercury lifted by the music sheet will thus be caught in the riftle and will drain back into the main trough.

Instead of having the Contact terminals 10 extend down flush with the lower guiding .surface of the tracker bar, they may be arranged with their .lower ends extending downwardsufficiently so that they Will be below the surface level of the mercury when the tracker bar is in its lower or operative position but above the lower ends of the holes in the tracker bar, as shown in Fig. There will thus be left a hole or recess 93 inthe"tracker bar beneath each contact terminal which is open to the under side of.

the tracker bar. The operation is the same as when the contact terminals extend down fiush with the .surface of the tracker bar except that the recesses beneath the ends of the terminal rods will become filled with mercury which will remain in the recesses when an imperforate part of the sheet is beneath them, and be lled at other' times when the perforation registers therewith.

The music sheet may be made of any Suitable material, but I preferably use a sheet of strong flexible paper which is treat- `ed vyitha substance,-suclras suitable oil or varnish, which will make the .paper less and increase its dielectric strength Without depriving it of the requisite flexibility. I prefer to treat the paper for this purpose with a sott or semi-Huid paraiiin, such as vaseline.

F rom the foregoing description it will be seen that an apparatus constructed in accordance 'with thepresentinvention, in addition to the general advantages and good qualities hereinhctore referred to, possesses certain important advantages contributing to the reliability and practically instantaneousaction of the apparatus, and avoids diticilliti s niet with in the use of other circuity` c ntrollers or transmitters employing a perforated controlling sheet or tape. All

such perforated-sheet controllers or-transmitters, so far as applicant is aware, make use of reading fingers or brushes Whichmcooperate with the perforations in the sheet, either to make contact directly through the fpert'orations or to cont-rol other contact de* vices. This makes the tracking of the sheet rough and irregular, the friction being very variable, and the fingers are liable to tear the perforated paper. With the apparatus of the present. invention, on the other hand, the tracking is perfectly smooth and regular. There is also much less danger from sparking with this apparatus, and oxidation by sparking is largely prevented by the tact that the break takesrplacebelow the surface of 7th@v merllr-yfor other conductin liquid "so that the paper is not to any considerable degree subject to theaction of the air; and direct heat from the spark is largely obvi'- ated by the presence ot a large metallic mass. Then, again, the break being below the surface of the mercury, a fresh clean contact surface isalvvays available, inasmuch as all impurities' in the mercury tend to rise to the surface. Another advantage of the present invention, as'compared With an apparatus employing the reading fingers, is that the full length ot the slot or perforation in the controlling sheet is available.' Where a reading linger is employed, the effective length -of the slot is reduced by an amount equal to the breadth of the point i or part of the reading finger that projects through the slot. In applicants apparatus, the circuit is closed practically instantaneously when the front of the slot reaches the contact-tern'1inal, and the circuit remains closed until the end ofthe slot passes the contact terminal. The full length of the slotis thus fully available, and in fact the apparatus will operate to,maintaiirthecil`- cuit closed for a time corresponding to the length of the slot plus the extent of the contact terminal lohgitudinally of the, direc tion of movement yof the perforated sheet.

The necessd lfy,v length `of theslots in the come trolling sheet is thus very considerably reduced,- and the weakening of the sheet correspondingly lessened. This feature of making the full length of the slot available, as -Well as other advantages here referred to, is oi .special value in the application of the invention Ito transmitting or controlling mechanism forv playing apparatus for musical instruments, since the length of the pertorations or slots in the music shcetbecome more' nearly proportional to the true time of the notes.

It will be seen from my construction that it is not necessary for the operator, in rcthreading the controller, to bring the hands into contact at all with the n'iercury in the trough. lVith the tracker-bar 22 in the elevated position shown in Fig. 5, the sheet may be readily passed below the lower sur face of the bar from the unwinding roll 27 to the winding-roll 28.-' It `will be 'further noticed, from Flg. 3, after the'trackerfbar has been depressed, and considering the sheet 23 as moving from left to right, that the upper surfade of the mercury is a curved one; or, in other words, I have a curved contact surface which conforms to, and accurately ts, the under curved surface of the perforated sheet. The top contact surface of the mercury is, therefore, a curved one'. It should also be observed that on account of the upward pressure of the mercury on the lower side of the music sheet there isl absolutely no danger of the mercury. Workf ing between the sheet and thetracker-bar 22.

. Bythe term guiding surfaces, as applied to the parts 25 and 26, I intend to describe them or refer to them as a spreading and smoothin surface for the music sheet, and not strict y as a guide. It will be seen that during the re-winding `movements the perforated sheet, as shown in lFig. 5, is out of contact with the mercury, or conducting 1i uid, and runs free from the roll 27 to the ro l 28, and barely touches the lowercurved surface of the tracker-bar 22. y The spreading or smoothing surfaces 25 vand 26 serve to hold the sheet elevated from the liquid.

" What is -claimed is 1. In a circuit controlling apparatus, the combination of a receptacleI containing a conductingiliquid, a single guiding surface facing downward in the .receptacle below the surface level of the li uid,-`a contact terminal in sal'd guiding sur ace, and means 'for moving a perforated sheet of non-conducting material against the downwardly facing guiding surface.

2. In a circuit controlling apparatus, the

y combination of a receptacle containing a .conducting liquid, a guiding member in the receptacle havin a guiding surface below the surface leve of the'liquid, a contact terminal in said guiding surface, and means for moving a .perforated sheet of 'flexible non-conducting material beneath said member and against said guidiug'surface.

3. In a circuit controlling apparatus, the combination of a receptacle A containing a condutting liquid, a single guiding member in the "receptacle having a downwardly facing, curved guiding surface below the surface level of the liquid, a plurality of contact terminals arranged insaid guiding surface, and means for moving a perforated sheet of non-conducting material beneath said member and against said, guiding surface. l

1i. In a circuit controlling apparatus, the combination of va receptacle containing a conducting liquid, a guiding member 1n the receptacle having a curved Vguiiding surface below the surface level of the liquid and l ing surface.

'having holes open to the guiding surface,

contact terminals in said holes extending downward to below the surface level of the liquid but' above the lower ends of the holes, and means for moving a erforated sheet of non-conducting material beneath said member and against said guiding surface. 5. In a circuit controlling apparatus, the combination of a receptacle containing a conducting liquid, a guiding member having a downwardly facing, curved guiding surface, a fixed Contact terminal in an open-v ing in said guiding surface, guide-Ways in the receptacle to permit said guiding member to move 'from a position above the li uid vertically downwardl to carry its gui in .surface below the sur acelevel of the li ui and means for moving a perforated` s e'et of non-conducting ntaterial beneath. said member and against said guiding surface.

6. In a circuit controlling apparatus, the combination of a receptacle containing a conducting liquid, a single guiding member i having a guiding surface, a eontactterminal arrangedin said guiding surface, means for moving the guiding memberv to carry its guiding surface into the liquid and .for retracting it to withdraw its guiding surface from the liquid, and means for moving a perforated sheet of non-conducting material against said guiding surface.

7. In a circuit controlling apparatus, the combination of a receptacle vcontaining a conducting liquid, a guiding member having a guiding surface, acontact terminal arranged in said guiding surface, means for :roving the guiding member to carry its guiding surface into the liquid and for automatically retracting the guiding member, and means for moving a perforated sheet of non-conducting material against said guid- 8. In a circuit controlling apparatus, the combination of a` receptacle-containing a conducting liquid, a guiding member having a guiding surface, a plurality of contact terminals arra'ngcd in said guiding surface, means for moving a perforated sheet of non-conducting material past said guiding surface, and means for movingthe guiding member downward to depress its guiding surface and the portion of the perfo-1 rated sheet adjacent thereto into the liquid.

9. In a circuit controlling apparatus,v the combination of a receptacle containing a conducting` liquid, a guiding mei'rber having a guiding surface, a plurality of contact terminals arranged in the guiding surface, means for moving a perforated sheet of non'conduct-ing material past said guide ing surface, means for moving the guiding member downward to depress its guiding surface and a portion of the perforated sheet. adjacent thereto into the liquid, and means controlled bv the perforated sheet for ductingmaterial, and a guiding/ device hav`r ingu guiding surface and a plurality of contact terminals in the guiding surface, said guiding device being mounted to move downwardl between said guides to carry its guiding surface and the portion of the per forated sheet adjacent thereto downward into and below the surface level of the liquid.

l1. In a circuit controlling apparatus, the combination of a receptacle containing a conducting liquid, a tracker bar having a curved undei` guiding surface and a plurality of contact terminals arranged therein, means for mov-ing a perforated sheet of nonconducting material past the guiding surface of the tracker bar, means for moving the tracker bar downward to depress its guiding surface and the portion of the perforated sheet adjacent thereto into the liquid and for raising the tracker bar to lift its guiding surface above the liquid, and means controlled by the movement of the perforated sheets for controlling the movement of the tracker-bar.

12. ln a circuit controlling apparatus, the combination 'of a receptacle containing a conducting liquid, a tracker vbar having a plurality of contact terminals arranged in its guiding surface, means for moving a perforated sheet of non-conducting material past the guidingsurfaceof the tracker bar,

meansffor moving the trackerbar do,Wniva'ildwM to depress its guiding surface and the portion of the perforated sheet adjacentthereto into the liquid and for raising the tracker bar to lift itsl guiding surface above the liquid, and means controlled by the tracker bar on its upward movement 'for reversing the direction of. theV movement of thee perforated sheet.

1?). In a circuit controlling apparatus, the lcombination of a receptacle containing a conducting liquid, a tracker bar having a plurality of cont; 'ft terminals arranged in its guiding surface, means for moving a perforated sheet of nonconducting material past said guiding surface, means for moving the tracker bar downward to depress its guiding surface and the adjacent portion of the perforated sheet into the liquid, means controlled by the perforated sheet for raising the tracker bar, and means controlled by the movement of the tracker bar for reversing the direction of movement of the perforated sheet.

14. In a circuit controlling apparatus, the combination of a receptacle containing a conducting liquid, a tracker bar havinga plurality of contact terminals arranged in its guiding surface, a carrying roll, a winding roll for drawing a perforated sheet of non-conducting material from the carrying roll past the guiding surfaceof the tracker' bar, means for moving the tracker bar downward to depress its guiding surface and the adjacent portion of the sheet into the liquid and for raising the tracker bar to lift its guiding surface above the liquid, dri-ving means for rotating the Winding roll for causing the forward movement of the perforated sheet and for rotating the carrying rollfor rewinding the sheet thereon, and means for controlling said driving means to causethe winding roll or the carrying roll to be driven according to the position of the tracker bar.

l5. In a circuit controlling` apparatus, the combination of a receptacle containing a conducting liquid, a tracker bar having a plurality of contact-terminals arranged in its guiding surface, supporting rolls for av perforated sheet of non-conducting material, driving means for 'rotating said rolls to more the perforated sheet past the guiding surface of the tracker bar, means for moving the tracker bar downward to depress its guiding surface and the adjacent portion of the perforated sheet into the liquid, means for automatically raising the tracker bar to lift its guiding surface above the liquid at the end of the forward movement of the perforated sheet, land means controlled by the movement of the tracker bar to cause one or the other ofthe carrying rolls to b driven by the driving means to cause the sheet to be driven forward or backward laccording to thegposition of the tracker bar. 1,6IiLa/circuit controlling apparatus, the combination of a receptacle containing a conducting liquid., a tracker bar having af plurality of contact terminals arranged in its guiding* surface, a carrying roll, a winding roll for drawing a perforated sheet of non-conducting material from the carrying roll past the guiding surface of the tracker bar, means for moving the tracker bar down Nvard to depress its guiding surface and the adjacent portion of the perforated sheet into the liquid, a driving motor, means for connecting the motor with the winding roll for causing the forwardmovement, of the perforated sheet, and means for disconnecting the driving motor from the winding roll and for connecting it with the carrying roll for causing the sheet to be rewound on the carrying roll. K

17. ln a circuit controlling apparatus, the combination of a tracker bar, a carrying roll, a windingA roll for drawing a perforated sheet, of non-conducting material fromY the carrying roll past the tracker bar, a driving motor, driving connections between the motorand the winding'roll and the carrying 18S In a circuit controlling apparatus,

the combination of a tracker bar, means for moving la controlling sheet past the tracker bar, means for moving the tracker bar into. operative position, means controlled by the controlling sheet for returning the tracker bar to its non-operative position, and electromagnetic means controlled by the movement of the tracker b'ar for effecting reversal of.

thedirection cf movem^nt of the controlling sheet.' i

19.' The `combination with a receptacie containing av conducting liquid, of a tracker bar 22 having a convexly curved under guiding'srface, contact terminals 10 arranged in tgiefnings in the tra-cker bar open to the gui ing surface of the bar, spreading or 2k smoothing surfaces 25 and 26, andi-.means forfeeding a perforated sheet of non-conducting material over thevsurfaces 25 and yand beneath -and against the guiding surface of the tracker bar and. between said guidinsurface and the 1i uid.

20. f the combination of a receptacle ntaining a conducting liquid tofbe electriczilly connected [with a. lsource ofelectrical energy, a tracker-bar having a curved under iding surface for guiding a perforated4 sheet through the liquid, a series yof contact terd minalsin said guiding surface,l each tov be connected with one 'of a vseries of electrically operated operating devices. c

21.111 a. 'circuit controlling 'mechanism, the `combination of a receptacle containing a conducting liquid tobe electrically connected with a source of electrical energy, a

tracker bar having an under guiding surface,

a series of Contact terminals in its guiding surface each to be connected Awith one of'a series of electrically operated devices, means for moving 'a perforated sheet past the tracker bar, and 'means for moving the tracker bar downward to depress its guiding surface and the adjacent portion of the sheet into the liquid and for raising the tracker bar above the liquid.

22. In a circuit controlling apparatus, the ccmbination of a receptacle containing a conducting liquid, a guiding surface in the receptacle below the surface level of the liquid, a contact terminal in an opening in 4.said guiding surface, means yfor moving a perforated sheet of nerf-conducting material against said guidingfsurface, a stretch-4 ing and smoothing surface for the perfo.

rated sheet as,it leaves the liquid, and a minor trough draining. into the main receptacle for receiving and returning to the to support a perforated sheet, a circuit control ing mechanism,v

. 24. In a circuit controlling apparatus, the y 'combination of a receptacle for containing ya conducting liquid, the sides ofwhichare curved away from the bottom portion of the receptacle, a tracker-bar provided with contact terminals, means, for elevatin and depressing the bar above and into the liquid', a-perforated sheet located below the trackerbar-and movabletherewith dou-n'into the liquid to lclose the circuit from the liquid to the contact terminals.

25. In a circuit controliingai' combination with a receptac a, conducting liquid, the opp( same being provided with atus, the leceiving ides of the d surfaces .an electrical terminal therein, means for depressing 4said bar into, and raising 4it from, the liquid, rollers for receiving thesheet and adapted to permit the same to move from one to the other in rewinding, and out of contact with the liquid when the trackerbar is. elevated.

' ,26. A circuit controlling apparatus having in combination, a mercury terminal to receive. a perforated insulating sheet, winding and rewinding means for the sheet, means to depress the sheet-below the'normal surface of said terminal when the controller is in use, and means to elevate the sheet for rewinding. l

27. In a circuit controlling apparatus, thecombination. with a receptacle for containing a mercury terminal to receive a perfo.- rated insulating music sheet, a tracker-bar having terminals therein for closing an electric circuit from the mercury terminal, means for elevating the bar above the mera tracker-bar,

cury electrode to permit the insertion of the' sheet Without immersiomand meansl to depress the bar and carry the sheet into con- Vtact with the mercury electrode.

28. An electric circuit controlling device comprising a receptacle, a conductingfluid in the receptacle, a tracker-bar, means for reciprocating the bar, a perforated music sheet'of insulating material interposed between the bar and the conducting fluid in the receptacle, whereby the movement of the bai" toward the conducting Huid will move a portion of the music sheet into contact with the conducting liquid.

mmiuaton of a trough @mami-ning an eccu conducng fiumi theiem, i permaied im? its maximal surface fo ca; ihre azcut L 

